1. Field of the Invention
The present invention relates to an oscillator calibration apparatus, and more particularly, to an oscillator calibration apparatus applied in an electronic device which utilizes two oscillators for operations.
2. Description of the Prior Art
In some mobile phones that have a memory in pixel (MIP) function or an active matrix organic light emitting diode (AMOLED) application, the driver integrated circuit (IC) built therein may have two oscillators with different respective frequencies. The oscillator with the faster frequency (e.g. 10 MHz) is used for the normal operations of the mobile phone; the oscillator with the slower frequency (e.g. 10 KHz) is used when the mobile phone is operated under a power-saving mode such as a hold mode in a MIP driver and a dimmed low power mode in a AMOLED driver.
Due to semiconductor process variations, the oscillators of the driver IC need to be calibrated before being delivered to the client. Calibrating the slower oscillator is time consuming, and the test cost is therefore increased.